Polyazo-dyestuffs



United States Patent 2,870,136 PQLYAZO-DYESTUFFS Walter Hanhart, Riehen, Switzerland, assignor to Ciba Limited, Basel, Switzerland, a Swiss firm No Drawing. Application April 7, 1955 Serial No. 500,014

Claims priority, application Switzerland April 14, 1954 7 Claims. Cl. 260-173) This invention provides new polyazo-dyestufis which like, for example, the dyestulf of the constitution in which R represents a benzene radical containing in para-position to the azo linkage a hydroxyl group and in ortho-position to the latter group a carboxylic acid group, R represents a benzene radical bound in para-position to the azo linkages, R represents a benzene radical bound in para-position to the azo linkages and containing in ortho-position to the azo linkage bound to the naphthalene nucleus a hydroxyl group, and X represents a primary amino group or an acylamino group.

The invention also provides a process for the manufacture of the new dyestufls of the Formula 2, wherein complex metal compound of the formula is demetallized. In Formula 3R represents a benzene radical containing in para-position to the azo linkage a hydroxyl group and in ortho-position to the latter group a carboxylic acid group, R represents a benzene radical bound in para position to the azo linkages, R represents a benzene radical bound in the 1,-, 3- and 4-positions to the groups -R N= OMe and N=N, X represents a primary amino group or acylamino group and Me represents a metal atom bound in complex union.

The metalliferous dyestuffs of the Formula 3 are obtained by treating a polyazo-dyestuff of the general formula R represents a benzene radical containing in para-position to the azolinkage a hydroxyl group and in orthm position to the latter group a carboxylic acid group,

7 2,5 dimethyl 4 amino 4' Patented Jan. 20, 1959 R represents a benzene radical bound in para-position to the azo linkages,

R represents a benzene radical bound in the 1-, 3- and 4-positions to the groups R -N=N.-, O=.-Alkyl and N=N, and

X represents a primary amino group or an acylamino group with an agent yielding metal, for example, an agent yielding cobalt, nickel or advantageously copper, under conditions such that an ortho:ortho'-dihydroXy-azo-metal complex is formed with the splitting up of the alkoxy group.

The polyazo-dyestufis of the Formula 4 areadvantageously prepared by coupling a diazo compound of an amino-monoazo-dyestuif of the formula with a primary amine of the formula (6) O-Alkyl and coupling the diazo-disazo-compound with Z-amino- 8-hydroxynaphthalene-6-sulfonic acid or a 2-acylamino- 8-hydroxy-naphthalene-G-sulfonic acid. The meanings of R R and R will be apparent from the definitions of these symbols given 'above. In the compound of .the Formula 6 the amino group is therefore in para-position to the carbon atom at which coupling occurs, and the alkoxy group is in ortho-position to the amino group.

As examples of amino-monoazo-dyestufis of the formula 5 there by he mentioned further diazotizing the resulting amino-disazo-dyestulf,

4-amino-4'-hydroXy-1,1'-azobenzene-3'-carboxylic acid,

4 amino 4 hydroxy-l,1'-azobenzene-3,3-dicarboxylic acid,

2 chloro. 4 amino 4 carboxylic acid,

2- or 3-methyl-4-amino-4-hydroxy-1,1-azobenzene-3'-carboxylic acid,

.2- or 3-methoxy-4-amino-4'-hydroxy-1,1'-azobenzene-3- carboxylic acid,

- hydroxy 1,1 azobenzene-B':

- hydroxy 1,1 azobenzene-.3'-carboxylic acid,

hydroxy 1,1 azobenzene-3'-carboxylic acid,

2 methyl 4 amino 5 methoxy 4' azobenzene-3-carboxylic acid,

'4 amino 4 hydroxy 5' methyl 1,1 azobenzene- 3-carboxylic acid,

4 amino 4' hydroxy 3'-carboxylic acid.

- hydroxy 1,1:

- 5' chloro 1,1' azobenzene- From the amino-monoazo-dyestutfs of the. Formula 5 and the amines of the Formula .6 there are obtained amino-disazo-dyestufi's of the formula (7) O -A1kyl as in the As amines of the F ula 6 there come into consideration, for example, the following compounds:

The coupling of the amines of the formula H-R NH andjthose of the Formula 6 with the diazo compounds or'the diazo-azo-compounds is usually carried out with advantage in a weakly acid medium, for example, an acetic acid medium. If these coupling components have only a weak capacity for coupling, it is of advantage to couple them in the form of their w-methane sulfonic acids and subsequently to split off the wrmethane-sulfonic acid group. s

The diazo-compounds obtainable from the amino disazo-dyestulfs of the Formula 7 may be coupled with a 2-acylamino-8-hydroxynaphthalene-6-sulfonic acid, for ex ample 2-acetylamino-S-hydroxynaphthalene 6 sulfonic acid, or advantageously with Z-amino-S-hydroxynaphthalene-6-sulfonic acid itself.

The diazo-disazo-compounds are coupled with the end components in an alkaline medium.

It is generally of advantage so to select the starting materials that the final dyestuffs contain a single sulfonic acid group, so that it is of advantage to use diazo-disazo compounds free from sulfonic acid groups.

The polyazo-dyestutfs of the Formula 4 so obtained are then treated with an agent yielding metal under conditions such that an ortho:ortho'-dihydroxy-azometal complex is produced accompanied by the. splitting up of the alkoxy group bound to the radical R For this purpose there may be used, for example, an agent yielding cobalt or nickel, but preferably an agent yielding copper. There may be used, for example, salts of divalent nickel such as nickel sulfate, salts of monovalent or divalent copper such as cuprous chloride or cupric sulfate, and also compounds which contain these metals in complex union. Especially suitable for this purpose are cuprammine complexes, for example, the complex nickel or copper compounds obtainable from ammonia or alkylamine such as ethylamine, or ethanolamine, morpholine, pyridine, a picoline or piperidine. In order that the alkyl group shall be split off completely from the alkoxy group with the formation of the metal complex of the trisazo-dyestutf, it is usually necessary to carry out the treatment with the agent yielding metal at a raised temperature, for example, at about 90 C. and for several hours. It is of advantage to work in an aqueous medium. If desired, the treatment with the agent yielding metal may be carried out in the presence of a suitable addition. As such additions there may be mentioned, bases such as ammonia or pyridine, for example an excess of the base which is present in the molecule of the metal-ammine complex, if the latter is used for the metallization.

The demetallization of the complex metal compounds may be carried out in a manner in itself known, advantageously by the treatment with a concentrated mineral acid, especially hydrochloric acid at the ordinary tem-. perature, or with a dilute mineral acid at a raised temperature, or by treatment with an alkali cyanide or alkali sulfide. When a mineral acidis used for the treatment the metal bound in complex union is converted into an easily soluble metal salt, which can easily be separated from the dyestufi sparingly soluble in an aqueous acid medium. It is generally of advantage to convert the dyestufl? so obtained into a soluble alkali salt thereof by treatment with an alkali, for example, sodium carbonate.

The polyazo-dyestufis of the Formula 2 are suitable for dyeing a very wide variety of materials, for example, animal fibers such as wool, silk and leather, but especially for dyeing or printing cellulose-containing materials, such. as cotton, linen and artificial silk or staple fibers'of regenerated cellulose. It is of advantage to treat the dyestuffs on the fiber or partially on the fiber and partially in the dyebath with an agent yielding metal by the generally known methods. There may be used with advantage, for example, the process of U. S. Patent No. 2,148,659, in which there are carried out in the same bath first dyeing and then the treatment with the agent yielding metal. As agents yielding metal there are preferably used those which are stable towards alkaline solutions, such as complex copper tartrates.

In some cases especially valuable dyeings can be made by using the process in which a dyeing or print produced with the metal-free dyestuff is after-treated with an aqueous solution which contains a basic formaldehyde condensation product of a compound containing at least once the atomic grouping for example, dicyandiamide or dicyandiamidine, or of a compound easily convertible into a compound containing the said atomic grouping, for example, cyanamide, and which solution also contains a water-soluble, preferably complex, copper compound. Such processes are described, for example, in British Patent No. 619,969.

It will be understood that combination dyeings can be produced by using a dyestulf of the invention together with another direct-dyeing dyestuff, for example, a dyestutf of the Formula 4 given above.

The following examples illustrate the invention, the parts and percentages being by weight unless otherwise stated and the relationship of parts by weight to parts by volume being the same as that of the kilogram to the liter: Example 1 O-CH: HO

N=N NH:

are dissolved in the form of the sodium salt in 300 parts of hot water with the addition of 5.5 parts of an ammonia solution of 24 percent strength. At C. there is added an ammoniacal solution of copper oxide consisting of 2.5 parts of crystalline copper sulfate, 10 parts of water and 4 partsfof ammonia solution of 24 percent strength, and the whole is stirred at that temperature for about 24 hours. The'precipitated copper compound of the ortho:ortho-dihydroxy-azo-dyestuff is filtered off, and rendered metal-free by stirring it with cold concentrated hydrochloric acid. After filtering off the dyestufi and washing it with water, it is converted into its sodium salt. When dry it is a black powder which dissolves in concentrated sulfuric acid with a blue coloration and in water with a black-green coloration, and dyes cotton by the single bath 'or 2-bath after-coppering process greenish black tints which are fast to washing and light.

' are dissolved at 95 C. in the form of the sodium salt in 300 parts of water and 5.5 parts of ammonia solution of 24 percent strength. An ammoniacal solution of copper oxide, consisting of 2.5 parts of crystalline copper sulfate, 10 parts of water and 4 parts of ammonia solution of 24 percent strength, is added, and the whole is stirred for 18-24 hours at 95 C. The completely precipitated copper compound of the ortho-ortho-dihydroxy-. azo-dyestutf is filtered off, dried and demetallized by stirring it with cold concentrated hydrochloric acid. The dyestuff is filtered off and washed, and converted into its sodium salt by stirring it with sodium carbonate in sodium chloride solution of 10 percent strength. When dry, the sodium salt is a dark powder which dissolves in concentrated sulfuric acid with a blue coloration and in water with a blackish green coloration, and yields on cotton black dyeings which are fast to Washing and light after treatment with a copper salt.

It is not essential to dry the dyestufi before demetallization, and it may be used in the form of a paste. The demetallization may be carried out equally well with hot dilute hydrochloric acid, for example, by heating the metalliferous dyestuff for several hours in hydrochloric acid of about 5 percent strength.

If sodium cyanide is used as the decoppering agent, the copper compound of the dyestutf need not be separated from the reaction mixture. Thus, there is added to the warm dyestufl? suspension a solution of 2 parts of sodium cyanide, the mixture is stirred for a short time at 60-65 C., and the dyestuif, which is completely dissolved, is precipitated by the addition of parts of sodium chloride per 100 parts by volume of solution.

Further ortho:ortho'-dihydroxy-azo-dyestuifs, which can be prepared in the manner described above by coppering accompanied by demethylation and subsequent demetallization, are given in the following table. The initial dyestuifs are obtained by coupling the diazo compounds of the amino-monoazo-dyestufis given in column I with the middle components given in column II, and further diazotizing the amino-disazo-dyestuffs and coupling the diazodisazo-compounds in an alkaline medium with the end components given in column III.

in 4000 parts of water 3 parts of acetic acidof kttlipercent strength and 3 parts. of crystalline copper sulfate. Finally, the dyeing is rinsed in the cold and dried. There is obtained a black dyeing of good fastness to light and washing.

What is claimed is: l. A polyazo-dyestufl of the formula in which R represents a benzene radical containing in para-position to the azo linkage a hydroxyl group and in ortho-position to the latter group a carboxylic acid group, R represents a benzene radical bound in para position to the azo linkages, R represents a benzene radical bound in para-position to the azo linkages and containing in ortho-position to the azo-linkage bound to the naphthalene nucleous a hydroxyl group, and X represents a member selected from the groups consisting of a primary amino group and an acetylamino group.

2. A polyazo-clyestufi of the formula HO O C in which R represents a benzene radical bound in para- I. Amino-monoazo dyestufi II. Middle component Example 3 100 parts of cotton are entered at 50 C. into a dyebath which contains in 4000 parts of water, 4 parts of the trisazo-dyestufi obtained as described in Example 1, and 2 parts of anhydrous sodium carbonate. The temperature is raised to 90-95 C. in the course of 20 minutes, 40 parts of crystalline sodium sulfate are added, and dyeing is continued for hour to one hour at 90-95 C. The dyeing is then rinsed in cold water and treated for 20-30 minutes at -70 C. in a bath which contains 75 H000 Y l-amino-Z-methoxy benzene.

l-amino-2,5-dimethoxyben- IV. Tint of the III. End component coppered dyeing on cotton 2-amino-8-hydroxy-naphthalene- Black.

fi-sulionic acid. d0 Greenlsh black.

... do Do.

. do Black.

do Do.

Green black.

2-acetylamino-S-hydroxynaphthalene-fi-sulfonic acid.

position to the azo linkages and R represents a benzene radical bound in para-position to the azo linkages and containing in ortho-position to the azo linkage bound to the naphthalene nucleus a hydroxyl group.

4. A polyazo-dyestutf of the formula (RH HO I HOzS in which R represents a benzene radical bound in paraposition to the a zo linkages and Y represents a member s electefl from: the group consisting of a methyl group and a methoiry g'roup.

5. The polyazo-dyestuff of the formula on E0 V H0O I 6. The polyazo-dyestufi of the formula 7. The polyazo-dyestufi of the formula References Cited in the file of this patent UNITED STATES PATENTS 536,878 Kirchhofl Apr. 2, 1895 2,242,456 Delfs et al. May 20, 1951 FOREIGN PATENTS 263,533 Switzerland Feb. 1, 1950 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No; 2,870,136 January 20, 1959 Walter Hanhart It is herebjr certified that error appears in the-printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 2 line 4 for the right-hand portion of the formula reading "'-=*=*O;Alkyl" read O-Alkyl columns 5 and 6, Example 2, in the table under the heading "L. Amino monoazo dyes'tuff' first item, for "-azobensene-" read -azobenzene- XSEAL) ttest:

KARL H AXLINE ROBERT C. WATSON Attesting Oificer 7 Commissioner of Patents 

1. A POLYAZO-DYESTUFF OF THE FORMULA 